How to execute my operator (wikibooks.org 2020)?
The code works just as it is supposed to work. You just need to enable Operator Search to use it. You need to select Edit -&gt; Preferences. Under Interface check Developer Extras checkbox.

Now you can find Operator Search from Edit drop down menu.

Search Add Tetrahedron


Errors
You can select Window -&gt; Toggle System Console to see the errors your code gives.